It is known from DE 39 30 171 C2 how to integrate the roll bar with the headrest so that the headrest is provided with a groove-like recess on top and at the side, which receives the roll bar when it is in its rest position. The roll bar then cannot be seen and does not detract from the safety.
In this familiar case, however, the headrest cannot be adjusted in height, which is a disadvantage. Integration of the roll bar in the headrest has the sole purpose of concealing the bar.
From DE 38 22 461 A1 a roll bar protection system has become familiar, which is integrated with the headrest such that the upper end of the U-shaped roll bar is configured directly as a headrest and secures a headrest cushion. This headrest cushion can be adjusted in height along the legs of the roll bar and relative to them. Due to its design, however, the headrest cushion can only be adjusted manually in height.
From DE 39 27 265 A1 there is known a power-operated headrest with integrated roll bar protection function, which can be moved continuously into different positions, driven by an electric motor, and from each position the roll bar protection system can be placed in the maximum end position in a danger situation. The known system has a housing of shaped sheet metal parts which can be screwed together with the vehicle""s superstructure and which is arranged behind the rear seats of the convertible. In the housing, a U-shaped roll bar in the form of an appropriately curved steel tube is movably mounted by means of guide rollers. The roll bar is provided with a head-support cushion, forming the headrest, i.e., it is likewise fully integrated with the headrest.
The roll bar engages with two driving compression springs, which are held in a pretensioned condition. An electric motor drive unit is arranged between the compression springs, firmly fixed to the vehicle, with gearing, toothed belt, and a pinion which engages teeth on the roll bar. The toothed belt is coupled to the gearing by a toothed wheel, which is driven by a coupling with radially movable ball elements by the shaft of a toothed belt drive which engages with the gearing. This shaft is connected to a trigger magnet, which in a danger situation separates the shaft from the toothed wheel in the coupling, so that the toothed belt is uncoupled from the gearing. This releases the roll bar, which is taken to its end position by means of the compression springs. This familiar roll bar protection system has the following disadvantages:
The basic elements of the roll bar system (case and bar) can only be produced with relative difficulty.
The drive arrangement for the continuous movement of the roll bar, the so-called comfort drive, which at the same time serves to adjust the height of the headrest, is relatively complicated and also relatively prone to repairs in respect of the toothed belt drive.
The release system between roll bar and release magnet to free the roll bar in event of a flip-over is complicated and can only be restored with difficulty to the initial condition after being released.
Continuous moving of the roll bar with the headrest influences the tension of the driving compression springs. In particular, when the bar is moved down, the electric motor must work against the pretension of the springs and must therefore be dimensioned sufficiently robust.
The purpose of the invention is to configure the roll bar protection system mentioned at the outset so that it can be made cost effectively, and have a simple drive arrangement for the continuous movement of the roll body and the headrest, not having any influence on the fast drive for a roll-over situation.
This purpose is accomplished according to the invention by a rollover protection system for motor vehicles that is coordinated with a seat of the vehicle, with:
an external box profile which can be firmly attached to the vehicle, forming a case for the components of the rollover protection system,
an inner box profile, supported so that it can move in the outer box profile by guide elements, being designed as the roll body, and accommodating a fast drive for extending into the upper end protection position, and
a drive arrangement for a continuous movement of the inner box profile, consisting of an electric motor/gearing arrangement with a threaded spindle of predetermined length, as well as a tie-bar which can move in the outer box profile, possessing a nut for active engagement with the threaded spindle, and being detachably connected to the inner box profile.
An especially simple and compact configuration of the roll bar protection system according to the invention can be achieved by integrating the headrest into the roll body, having a head support cushion forming the headrest molded on the upper piece of the inner box profile.
In theory, however, the headrest can be separate from the roll body, in that, besides the inner box profile, and in parallel with it, there is at least one additional lengthwise molded body secured to the tie-bar, guided in the outer box profile, on which a head support cushion constituting the headrest is formed, in front of the inner box profile facing the passenger.
In order to properly guide the inner box profile in the outer box profile, according to one configuration of the invention the system is configured so that guide rollers are arranged as guide elements on the inner box profile and guide grooves are formed in the outer box profile to accommodate the guide rollers and the tie-bar.
The fast drive of the system can essentially be formed by the familiar components. An especially simple and effective system can be achieved according to a further modification of the invention if the fast drive is formed by a pretensioned driving compression spring, which is arranged in the inner box profile, and which is supported by one end (the upper one) against an upper crosspiece of the inner box profile, while its other, lower end, is firmly joined to the tie-bar and if the inner box profile is connected to an actuator by a release system which releases this box profile in event of danger, being firmly mounted on the tie-bar.
Thanks to this design, therefore, the fast drive in a state of danger can reliably move the inner box profile to the upper protected position with simple means, in any given position of the tie-bar.
There are several conceivable design solutions for connecting the inner box profile via the release system to the actuator on the tie-bar and for locking this box profile after the release to prevent an unintentional resetting. An especially simple construction can be achieved by a further modification of the invention, if a locking latch with a toothed profile is linked by a shaft on the inner box profile, which is detachably connected via the release system to the actuator when it is activated in the danger situation, and if a toothed rod is firmly arranged inside the outer box profile, which can interact with the toothed profile of the locking latch in event of danger after the releasing of the locking latch by the release system, thanks to compression springs engaging with the locking latch.
This design requires only a few structural pieces, which can be made without major expense and which also enable relatively easy installation.
There are various possibilities available for the configuration and linking of the locking latch. A first embodiment results, according to a further modification of the invention, if the locking latch is fashioned as a two-arm lever, with an upper arm that is longer and a lower arm that is shorter relative to the linkage, there being arranged the toothed profile on the longer upper lever arm, with which the compression springs engage, and on the shorter lower lever arm a detent bolt for a detachable engagement with a hook-shaped locking element of the actuator, forming the release system.
A second, more favorable possibility for the distribution of forces results, according to a further modification of the invention, when the locking latch is fashioned as a single-arm lever, being linked at its upper end to the inner box profile by the shaft, which is provided with the toothed profile in an intermediate segment with which the compression springs engage, and at its lower end there is arranged a [noun omitted] for a detachable engagement with a hook-shaped locking element of the actuator, forming the release system.
The construction of the above-described locking system, therefore, possesses the following essential characteristics:
Locking latch and detent bolt form a single unit
The system of tie-barxe2x80x94actuatorxe2x80x94locking latchxe2x80x94detent boltxe2x80x94compression springsxe2x80x94inner box profile forms a single unit for the comfort mode.
This system is separated into two individual components by the release of the actuator.
A remote-control reversal of the fast drive system is possible through the electric drive of the tie-bar.
There are a number of possibilities for the arrangement of the roll bar protection system in the vehicle.
According to a preferred embodiment, it is possible to integrate the system in the seat of the vehicle in simple fashion by having both the inner and outer box profile curved in a circular arc, and the outer box profile being fastened behind the seat, preferably to the rear wall of the vehicle.
But it is also possible to configure the box profiles in linear fashion, and to mount the outer box profile forming the case directly behind the seats of the vehicle.
Other characteristic features of the invention will emerge by the description of a sample embodiment represented in the drawings.